Rigid braces are known which, when put into place, permanently maintain the limb in the extended position. These devices make it possible to stand up to walk, but they do not allow for a normal sitting position.
There also exist hinged braces comprising a thigh-piece and a legging which are hinged together about an axis to allow the knee to bend. In order to provide support in the standing position, such braces include means for maintaining or urging the thigh-piece and the legging into an extended position relative to each other. These means may be constituted by a mechanical latch which, when in operation, prevents bending and which needs to be released before the patient can sit normally. Braces of this type, like those of the rigid type, provide for very stiff walking; and whenever the patient desires to sit down normally, it is necessary to manipulate the brace. Such manipulation requires specially adapted clothing and is difficult for a handicapped person to perform since use is generally also being made of at least one walking stick or crutch.
In other braces, the latch is replaced by resilient return means tending to return the brace to its extended position, and formed, for example, by a splint pressing against the front face of the knee. This arrangement provides for walking which is less stiff, but it is still necessary to perform manipulations in order to achieve a normal sitting position, i.e. the splint must be disconnected, and this gives rise to the same drawbacks as mentioned above.
The invention seeks to avoid these drawbacks of prior knee braces.
Another aim of the invention is to provide a knee brace which allows the leg muscles to work and thus enables the leg to recover its normal functions over a period of time.